Just sing the theme song from the cheesy Sid & Marty Kroft kids show: "Marshall, Will and Holly/On a routine expedition/Met the grea-test earthquake/ever known …" And from there they plunge into a parallel dimension where they are menaced by Sleestak lizard people, a Tyrannosaurus rex named Grumpy and a furry little guy called Chaka, who is supposed to be friendly, but maybe not this time.

Based on your statement: its a option that all body parts had to react to a new universe. so its possible our present eye is a change from the original. like women acquiring changes that made them newly have grea birthing pains.